5.3.3. Using Yum Variables
You can use and reference the following built-in variables in yum
commands and in all Yum configuration files (that is, /etc/yum.conf
and all .repo
files in the /etc/yum.repos.d/
directory):
$releasever
You can use this variable to reference the release version of Fedora. Yum obtains the value of $releasever
from the distroverpkg=value
line in the /etc/yum.conf
configuration file. If there is no such line in /etc/yum.conf
, then yum
infers the correct value by deriving the version number from the redhat-release package.
$arch
You can use this variable to refer to the system's CPU architecture as returned when calling Python's os.uname()
function. Valid values for $arch
include: i586
, i686
and x86_64
.
$basearch
You can use $basearch
to reference the base architecture of the system. For example, i686 and i586 machines both have a base architecture of i386
, and AMD64 and Intel64 machines have a base architecture of x86_64
.
$YUM0-9
These ten variables are each replaced with the value of any shell environment variables with the same name. If one of these variables is referenced (in /etc/yum.conf
for example) and a shell environment variable with the same name does not exist, then the configuration file variable is not replaced.
To define a custom variable or to override the value of an existing one, create a file with the same name as the variable (without the “$
” sign) in the /etc/yum/vars/
directory, and add the desired value on its first line.
For example, repository descriptions often include the operating system name. To define a new variable called $osname
, create a new file with “Fedora” on the first line and save it as /etc/yum/vars/osname
:
~]# echo "Fedora" > /etc/yum/vars/osname
Instead of “Fedora 20”, you can now use the following in the .repo
files:
name=$osname $releasever